We had to pay the 1st installment of this before probate was granted on my MIL's estate. We just about had the funds to do this (although not sure what people are s'posed to do if they haven't). We haven't yet sold her house, however, and until we do so, are not going to be able to pay any more. When will we be expected to cough up? Will the tax office wait until the house sale is completed?